This invention relates to the manufacture of solar collectors, and particularly to the manufacture of solar heating devices of a type in which sheets of thermoplastic material are formed into flexible wall containers for fluid to be heated.
It has now been proposed to provide a solar fluid heater for use with a variety of types of solar heating devices and which is constructed of extremely lightweight reinforced thermoplastic material which exhibits unusual properties of strength and chemical inertness. Such devices are proposed as having a flexible wall construction and as being made from fabric reinforced sheets of fluoroplastic material such as polytetrafluoroethylene (also known by the trademark Teflon) fusibly bonded together to provide fluid flow passages therebetween. Such solar heating devices are recognized as having substantial advantages over the rigid pipe heaters more commonly encountered.